Susceptibility in vitro of clinical Candida albicans isolates to the selected azoles

Candida spp. is the most prevalent cause of fungal infection worldwide, and their increasing resistance to anti-fungal agents, especially to azoles, has become problematic. The aim of this work was to establish the susceptibility to fluconazole, itraconazole, voriconazole and posaconazole of 50 clinical C. albicans isolates from hematooncological patients. This has been evaluated using the following parameters: MIC (Minimum Inhibitory Concentration), MIC₅₀ (MIC required to inhibit the growth of 50% of organisms), as well as MIC₉₀ (MIC required to inhibit the growth of 90% of organisms). Susceptibility of the studied clinical isolates to all azoles was high, being 86% for itraconazole, 90% for fluconazole and posaconazole and 92% for voriconazole. The resistance rates ranged from 8% (voriconazole), to 12% (itraconazole). The emergence of azole-resistant yeast strains creates a necessity to determine and monitor the sensitivity of the isolated Candida spp., including C. albicans, especially in patients predisposed to life-threating fungal invasive disease.